ZCash (formerly Zerocash/Zerocoin) technology preview

How about I just stick to actual money?

The zero-knowledge proof itself offers statistical privacy in the face of unbounded (so more powerful than quantum) attackers. So surprisingly, you are mostly fine. But you would need to take two steps to protect yourself. First, you have to use each zcash address only once.

Second, you need to use a post quantum secure means of notifying the recipient they got a transaction and of the coin commitment openings. The built in mechanism in ZCash, which posts a ciphertext to the blockchain encrypted under the recipients public key is standard off the shelf public key cryptography. It's efficient, but is of course not post quantum secure. Nothing requires that you use this mechanism, however. You can always post a garbage ciphertext and inform the recipient some other way.

It's time to have a serious conversation about whether this is actually true when it comes to financial privacy.

Our society is governed by money. Money governs our production directly, and it governs our regulations indirectly since votes can be purchased. Governments derive their power from the consent of the governed, but we use money that doesn't allow us to withdraw our consent without opting out of the economy entirely. Your complaints about money in politics or unstoppable violent cartels around the world are complaints about tyranny, and we should be fighting that tyranny.

Anonymous currencies go in the other direction. I'm glad people are building them, but we need to start talking about the implications of using them. Everything about our society will be decided by the people with the most money if people accept anonymous currencies. Democracy isn't possible when you can't hope to detect when influence is being purchased.

We're already most of the way there: dollars are anonymous to everyone except the governments that regulate banks. Since those governments have been purchased, those regulations can only really be used against those who haven't already purchased strong representation in the government already.

I think we need to go in the opposite direction. We need currencies that everyone can track so individuals can decide whose power they'd like to submit to. If I know someone is buying influence and I want to reject their power to do so, I can stop accepting any money they've used in that way. People accept money to influence politics because other people will accept that money. If other people stop accepting that money, it won't be possible to buy influence anymore. The people who sell their goods, services, and labor will set the rules by their decisions about what money to accept. Wealth won't govern our society, production will.

This is merit capitalism. I think it's closer to the world we want to live in. I hope you'll join me in reconsidering whether financial privacy is actually a good thing.

http://meritcapitalism.com/